As a class, please post your answers to PS 3. Show as much detail as needed to ensure everyone can understand how you arrived at your answer. I will post my comments as needed. (M. Grdinic)
1a. 78 cm to m: I set up my conversions like this (see below), after multiplying 78 and 1, i took the product (which is 78) and divided it by 100. The centimeters unit cancels out and the final answer becomes .78 meters
78cm
1m
100cm
(Matt C.)
1b.200.5mL to L. I set up my conversions as 1000 mL=1 L. I multiplied 200.5 and 1, and then I took the product 200.5 and divided it by 1000. The mL units cancel out, leaving the final answer of: 0.2 L (this is because 1000 only has 1 significant figure).
200.5mL
1L
1000mL
-Edward Kang
1c. 50"u" m to mm. I know that 10^6 "u"m is equal to 1 m. So if I change that conversion to fit the mm scale (which has 3 less digits), 10^3 "u"m=1mm. I multiplied 50 "u"m by 1 and using the product I divided 50 by 10^3. The result was 0.05 mm.
-Edward Kang
50"u"m
1mm
10^3"u"m
1d. 750cg to g. Using the conversion factor of 100 cg=g, I set up my conversion factor. Next, I multiplied 750 by 1, then divided by 100. The result was 7.5 grams. -Edward Kang
750cg
1g
100cg
-Josef Niemann
1e) Using formula D=Mass/volume where mass = 14.0g and D= 10.5cm3 (10.5g / cm3= 14.0g / volume cm3) 14.0/10.5 = (1.3cm3)
1f. "How many seconds are in a one 24 hour day?"
Since all units of conversion have infinitely many significant digits, rounding is not necessary. After canceling units, I got 86400 seconds.
60 seconds
60 minutes
24 hours
1 minute
1 hour
1 day
(Andrew Blank).
1g) 10mph to meters per second
10 miles
1 hour
1609.344 meters
16093.44 meters
268.224 meters
1 hour
60 seconds
1 mile
60 seconds
1 second
I set a dimensional analysis chart with the conversion factors of hours to seconds and miles to meters.
(Marielle Billig)
2. 72 in. to mm
Using the conversion rate of
1 inch = 25.4 millimeters, I set up a dimmensional analysis chart:
72 in.
25.4 mm
1 in
I simply multiply 72 * 25.4 and get 1800 mm because 72 only has 2 significant figures.
(Arin K.)
3. Use the conversion rates 1 stone=14 pounds and 1 stone=6.35029318 km
14 stone
14 pounds
1 stone
Multiply 14*14 to get 200 pounds because 14 only has 2 significant figures.
14 stone
6.35029318 kg
1 stone
Multiply 14*6.35029318 to get 89 kg because 14 only has 2 significant figures
(Ethan M.)
4. 2.75 angstroms to meters
Used the conversion rate 1 meter=10^ -10 angstroms
set up a dimensional analysis chart:
2.75 angstroms
10^ -10 meters
1 angstrom
Multiply 2.75*10^ -10 to get .000000000275 meters because 2.75 has 3 significant figures
As a class, please post your answers to PS 3. Show as much detail as needed to ensure everyone can understand how you arrived at your answer. I will post my comments as needed. (M. Grdinic)
1a. 78 cm to m: I set up my conversions like this (see below), after multiplying 78 and 1, i took the product (which is 78) and divided it by 100. The centimeters unit cancels out and the final answer becomes .78 meters
1b.200.5mL to L. I set up my conversions as 1000 mL=1 L. I multiplied 200.5 and 1, and then I took the product 200.5 and divided it by 1000. The mL units cancel out, leaving the final answer of: 0.2 L (this is because 1000 only has 1 significant figure).
1c. 50"u" m to mm. I know that 10^6 "u"m is equal to 1 m. So if I change that conversion to fit the mm scale (which has 3 less digits), 10^3 "u"m=1mm. I multiplied 50 "u"m by 1 and using the product I divided 50 by 10^3. The result was 0.05 mm.
-Edward Kang
-Edward Kang
1e) Using formula D=Mass/volume where mass = 14.0g and D= 10.5cm3 (10.5g / cm3= 14.0g / volume cm3) 14.0/10.5 = (1.3cm3)
1f. "How many seconds are in a one 24 hour day?"
Since all units of conversion have infinitely many significant digits, rounding is not necessary. After canceling units, I got 86400 seconds.
1g) 10mph to meters per second
(Marielle Billig)
2. 72 in. to mm
Using the conversion rate of
1 inch = 25.4 millimeters, I set up a dimmensional analysis chart:
(Arin K.)
3. Use the conversion rates 1 stone=14 pounds and 1 stone=6.35029318 km
(Ethan M.)
4. 2.75 angstroms to meters
Used the conversion rate 1 meter=10^ -10 angstroms
set up a dimensional analysis chart:
-Daniel Newman